Introduction: Safety Penny Fakething
Runner Up in the
Park Tool Bike Month
A modern take on that classic bicycle design.
Step 1: Starting the Frame
Select a scrap frame & forks. Cheap 'gaspipe' MTB frames are easy to weld. Remove the forks and assess how it will go together.
Step 2: Bending the Forks
The forks will have to be bent to match the frame. Forks are tough, so use levers to bend them.
IMPORTANT: Unless you are tall (like me) you may need to bend the top-tube and down-tube of the frame in to make it smaller - in this case you will have to cut the frame first.
Step 3: Cutting the Frame and Forks
The frame & forks can be cut so that they fit together. A normal hacksaw can be used, or a pipe cutter.
Step 4: Joining the Frame
If the sizes of tubes that are to be joined are a match, then a short piece of smaller tube can be used inside them as a ferrule to help line the joint up and add strength. If the sizes don't match, then one tube can be welded inside the other. This will make a less attractive weld, but, so long as the weld is strong, you can fair the shapes with car body-filler (bondo).
Step 5: The Armature
The armarture, or spine, will need to be made from strong tubeing. I used 40mm ERW steel tube - this is probably the minimum that you could get away with.
It was bent using a hydraulic tube bender. If you are lucky, you may find some scrap that is already bent to a suitable shape.
I welded the headtube in before I did the second bend, so that I could assess the shape more easily.
Step 6: Finishing the Frame
You will need to weld a set of front forks into the end of the armature, to take the smaller rear wheel. My Penny fakething uses a 12" wheel.
A footpeg, made from scrap tubing, can also be added.
The saddle also needs to be considered. I wanted mine above the head tube so that I could slide off forwards to dismount. It also needs to be placed so that your weight is evenly distributed.
Step 7: Handlebars
My 'Safety' fakething uses step-through handlebars.
You could just put normal handlebars back in the steerer tube, but if you fall forwards, be prepared for a face-plant!
Other pennyfakething designs have the handlebars welded to the front frame section and are positioned under the seat. In this case, the rider has to 'step round' the bars when they mount the bike, so that the bars are below their legs.
The stepthrough bars were cut from the legs of an office chair, and needed a small ammout of bending to get the shape right.
They are held in a handlebar stem that has been welded into the seat tube. I found that clamping them was not strong enough.
Step 8: Riding
I found the best way to learn, was to scoot the thing along, and ride on the footpeg to gain confidence.
Then you have to go for it. Check it is in a low gear, and that your life insurance is up to date.
We have a be nice policy.
Please be positive and constructive.